BERLIN (AP) – A Russian man who worked at a German university has been arrested on suspicion of espionage for allegedly passing information to Russian intelligence, German prosecutors said Monday.

The suspect, identified only as Ilnur N., was arrested on Friday, and his home and workplace were searched. Federal prosecutors said he worked as a research assistant for a science and technology professorship at a German university. They didn’t identify the university or specify where in the country he was arrested.

The man is accused of meeting at least three times with a member of a Russian intelligence service, which prosecutors didn’t identify, between October of last year and this month. In two of those meetings, he is alleged to have handed over information on the university in exchange for an unspecified amount of cash.

A judge on Saturday ordered the man kept in custody pending a possible indictment.

Relations between Berlin and Moscow have been tense over recent years. Reasons have included allegations of Russian involvement in the 2015 hacking of the German parliament, a 2019 incident in which a Russian is accused of killing a Georgian man in downtown Berlin on Moscow´s orders, and the poisoning last year of Russian opposition leader Alexei Navalny. Navalny was flown to Berlin for treatment.